The invention relates to a process for treatment of objects, in particular disk-like objects such as metal sheets, glass panes, PCBs and ceramic substrates, where the objects are supplied to a bath containing fluid, rotated by means of a rotation device about the rotational axis of said rotation device with permanent alignment of the objects on said rotational axis, and at the same time transported through the bath and moved away translationally after the bath, with the objects being retained, during their transport through the bath in receptacles of the rotation device that are radial relative to the rotational axis, by a securing element peripherally surrounding said rotation device. The invention also relates to a device for treatment of objects, in particular disk-like objects such as metal sheets, glass panes, PCBs and ceramic substrates, comprising a bath fillable with fluid such as a chemical bath for treatment of the objects, a feed device arranged upstream of the bath, a conveying device passing the objects through the bath in the form of a rotation device with radial receptacles intended for receiving the objects, a securing element provided inside the bath and extending in the peripheral area of the receptacles for retaining the objects in the receptacles, a removal device arranged downstream of the bath, and the washing and/or drying stage arranged downstream of the bath with associated transport device.
In order to treat, for example, oxide layers of semiconductor wafers by etching in diluted hydrofluoric acid, it is known to place the wafers in hurdles made of plastic and then to successively immerse these either manually or with a handling unit in various chemical baths or to spray them with chemicals. The drawback of this procedure is that the placing of the wafers into the hurdles and the removal of the wafer from these hurdles necessitate additional procedural steps which are particularly unwelcome when the processes preceding or following the chemical treatment are to be performed continuously.
A further drawback of the known process is that the supply of chemicals to the wafers being treated is restricted by the hurdles. In addition, fluids like water and residual chemicals can remain in the pockets of the hurdles during drying unless expensive drying processes are used.
In another known process, the wafers are passed by a belt conveyor or transport belt through a spray device in which they are sprayed with chemicals. On the one hand it is not assured by spraying that the wafers are completely wetted, and on the other hand the treatment duration is restricted and/or the necessary equipment must be designed with a very high volume.
DE-PS 639 104 describes a device for the treatment of metal sheets that are passed through a bath filled with liquid. Here the flat objects are picked up by a rotation device and passed through the bath. Downstream of the bath is a transport device with which the objects are moved translationally. The rotation device itself is supplied with the objects from a stack. Furthermore, stationary guide strips run peripherally to a rotation device, along which the metal sheets slide in order to ensure that these metal sheets remain inside the rotation device.
A transport device is known from EP 0 070 694 A1 in which objects such as sockets are transported by means of a rotary plate that is surrounded on the circumferential side by an endless belt. The rotary plate itself is rotatable about a vertically running rotational axis. The objects are moved in the entry area of the rotary plate relative to a fixed guide plate.
A spoked-wheel transport device described in DE-OS 1 951 200 provides for a conveying device in the form of a spoked wheel for cooling slabs.
A process for metallization of the surfaces of flat objects is described in DE 35 43 286 C2. The objects here pass through several cleaning and drying stations.
A device for turning PCBs is known from EP 0 637 561 A1, in which a rotating wheel in the form of a fan-shaped magazine is used. Here the objects are conveyed translationally to the magazine and then inside the latter above the rotational axis.